It isn't a movie. It's a still. That's why it's showing up as a still. Yes, it is a moving panorama, but a QT VR is basically one large still...stitched together from a bunch of stills, that you can pan and zoom...move. It isn't video. That's why all the normal tools that deal with video don't work on it.

Here is a VR video converter that works well on any VR videos downloaded from different sources. If you need to convert VR video to/from common video format like MP4, you can give it a try. Here is a detail guide: Best VR Video Converter for Converting Virtual Reality Videos